Curling tool for automobile body construction



Feb 26, 1929.

O. J. GROEHN CURLING TOOL FOR AUTOMOBILE BODY CONSTRUCTION Filed Jan. x

Patented Feb. 26, 1929.

UNITED STATES 1,703,618 PATENT OFFICE.-

OTTO JOHN GROEHN, OF DETROIT, MICHIGAN, ASSIGNOR TO HUDSON MOTOR CAR COMPANY, F.DETROIT, MICHIGAN, A CORPORATION OF MICHIGAN.

CURLING TOOL FOR AUTOMOBILE BODY CONSTRUCTION.

Application filed January This invention relates to a curling tool, particularly, although not exclusively, adapted for use in automobile body construction for curling or bending the juxtaposed free edges of superimposed metal strips. In the construction of certain types of closed automobile bodies formed from shaped metal panels, the adjacent or proximate edges of contiguous metal panels are formed with inturned flanges and the joints between the panels at the outer side are finished by means of molding strips constructed to form a bead or enlarged head concealing the joint between the panels and having inturned superimposed flanges or plates interposed between the inturned flanges of the panels. The free edges of the molding strips project beyond the free edges of the panel flanges and are bent or curled thereover to form a rigid interlocking connection. An object ofthe present invention is to provide a tool adapted to readily and effectively bend the projecting free edges of the molding strips over the edges of the inturned eration adapted to form beads or'tubular re.-

silient portions at opposite sides of the panel flanges, as a result of which a stronger and more rigid interlocking. connection between the flanges and molding strips is provided.

" 0 One of the important features of the present improved tool or curling die resides in the provision of means for curling or bending the edges of the superimposed molding strips over the edges of a pair of plates or flanges between which the strips are held and in which the tool is provided with a hook adapted to penetrate the molding, or to hook or catch behind a portion thereof so as to hold the tool in operative position, In addition, this hook serves the purpose of exerting an inward reaction to the outward thrust of the bending die, tending to draw the parts tightly into position, and, if desired, afterthe curling operation all of the superimposed strips and flanges may be secured together by rivets or bolts inserted through alined holes previously formed therein.

' Other objects of this invention will appear in the following description and appended claims, reference being had to the accompanying drawings forming a part of this specification, wherein like'reference charac ters designate corresponding parts in the several views, and wherein:

" Fig. 1 is a longitudinal section illustrating panel flanges, and preferably by a curling op- 26, 1926. Serial No. 83,960.

acurling tool embodying my invention and in operative position.

Fig.2 is a plan view, partly broken away, illustrating the construction shown in Fig. 1.

Fig. 3 is a fragmentary sectional view illustrating the parts at the completion of the curling operation. v

Fig. 4 is a fragmentary sectional view illustrating a panel construction with a molding interlocked and secured thereto.

Before explainin in detail the present improvement and mode of operation thereof, I desire to have it understood thatthe invention is not limited to the'details of construction and arrangement of parts which are illustrated in the accompanying drawings, since the invention is capable of other embodiments, and that the phraseology which I employ is for the purpose of description and not of limitation.

In certain types of closed automobile bodies, the enclosed body portions thereof are constructed'of sheet metal panels which are finished and reenforced by moldings at .the joints between the adjacent panel sections. As'illustrated in the drawings, the panels a and b of the automobile body are formed at the adjacent edges thereof with inturned flanges c and d, respectively. The molding may be of any suitable form and is preferably T-shaped in cross section and may be formed by folding a strip of sheet metal upon itself to form a curved bead or head f and inwardly turned superimposed flanges or a two-ply flange g and h which are held between the 0 flanges 0 and d of the panels. It will be. seen that the bead or head 7 of the molding strip overlaps the adjacent marginal portions of the panels engaging the outer surfaces thereof and provides a means'for' concealingand 96 finishing the oint therebetween. The flanges g and hof the molding preferably project a substantial distance inwardly beyond the free edges of the panel flanges c and (Z, and these edges of the molding are bent or curled in 100 opposite directions so as to. embrace and enclose the free edges of the flanges c and d, thereby providing a strengthened interlocking connection between the parts.

In accordance with the present invention I have provided a tool particularly adapted for the purpose of curling or-bending back the projecting edges of the superimposed molding flanges hand it, these ed es y means of the present improved tool ein'g sailed to 9 form tubular beads or rolled edges G and H (see Figs. 3 and 4) at opposite sides ofthe 1 panel flanges. Referring to Fig. 1', the

present improvedtoolcomprisesa chamberedsupport or casing. means of a cap 21 threaded thereto and having a centralchamber- 22W-ithinwhich-open structed'at the working face thereof to bend back or curl'the tree edges of the molding flanges g and h. The working endlofthe hammer or die member 26'is providedwith a pair oftangentialarcuate surfaces or grooves 26 and 26 separtedby means-of a tapered riih-or wedge 26". As clearly seen from Fig. 1, t-he tapered relatively sharp rib or'wedge 25" of the die ls adapt'ed to enter between and separate the free edges of the molding flanges g and'h, as shown at m, and these edges will be curledrearwardly'over the edges of I the panel flanges c and (Z, torming'beads G and H concentric with the curved dielaees 26""and26 V The casingor support 20 of the toolis provided'with a forward extension 27'locate'd at.

one side o'ftlie path of movement ofthe die onhammerfld Mountedon the upper tree of the extension 26 is a holder or block 28 V tellllllliltlng'ttt lllS'fOIWzHClGIlClIH an upward guide drilledtoreceive' a stud 3l forming a hook; This hook at itslowerendris' provided: with; a flange 32 housed within a counterbore of the member '30, andthe'latter is immovablysecuredto the extension'27l by, means of setscrews 29. From-this constructionit will be seen thattheforward ends of the extension 27 and the. guide 30 form ta'con tinuous vcrtical'face adaptedto abut against the paneLZ), andthe'upperend ofthe guide 30is formed with ahorizontal face adapted to fit against the inturnedflange d ofthe-panel 7); Thus, the-forward endof theguide'30 is so "formed as to fitintothe angle o ftlie panel bandits inturned fian 'e (Z, thereby properly positioningithe tool *wi h irespectto' the mold irig. flanges g' and k. The superimposed flanges 0, (Z, QIflITHIl/t of'the'panel's and mo'ld ingistrip are previously provided withver tically alined holes K therethrough through which maybe inserted bolts or'tubularrivet's' R. (see Fig. 4) after theourlingoperation so as to secure the parts together. Thehook 31 is adapted to be" inserted through the ,aliiied holes K in themolding and panel flang'es,=.thereby-enabling; the toolto be held against. the work during operation and cans ing the molding flanges to be bent" or curled between the die 26 and the hook 311 In the present instance, thepist'on 23'is 2O closed at one end by or chamber37'separatecl by means of a partition 39. This partition has apassage therethro'ugli controlled by means of. a suitable valve 38 provid'edwith a. stem aOprojecting through "a'ho'le drilled in the wall of the h'andle'ii li The outer'end ofthe valve stem 40-is engaged by alevenlpivoted art-.42 to the" handle support, and by! swinging the! lever e1 inwardly the valve. 38" will be'opened against the action-of the compression spring 453 interposed Between a" shoulder formed a on the valve and thebottom of a chamber 44in a remov-able'plug e5."

In the operation of the present nnproved tool, it will be'se'en that the'p'rojecting stud 31 forms a hook which maybe'inserted hy the operator through the vertically alined holes K in thepan'elflanges o and d ancl the moldin'g'fianges g and with-the angular guide '30 "fitting into the corresponding angu lar corner'formed loy thepanel b a.ncl'1ts'1nturned flange (1; Thereupomthe operator presses downthe handlelever-41so as toopen the valve 38" and" admit-jfiuidunder' pressure from the passagegti into thepassagefir'j re sulting in" shifting the piston 23* forwardly against the action of spring 25' The forward movement of the piston" will shiftthe hamlnerxor' die' 26 forwardly causing; the V- shaped rib or wedge 26 of the dieto separate the freeedge's oi the moldingfi anges g-and h; The-continuedforwardmovement of the die 26 will curl themoldingstripsrearwardlyin the manner shown in Figs. 8-and e. Ttwill also 'benot'edthat the hook 31 act-sto 'hold the flanges g and 72; ofthe nioldingstrip' against the action of-the -die*or hammer 26, thereby: exerting an inward reaction to; the outward thrust-of said die or hammer and drawing the head 7 of the molding-"into close engagement with-the outerfaces otthe'panels, this operation being permitted by making the holesK in the panel fianges'slightly larger than the-corresponding holes inthe molding flanges, as shown: Upon completion of this operation, the holes Kthrough-the several flanges-'0; (Z; gan d h"w-i1l be properly alined to permitreception of a bolt or rivetR means of which the parts are *secured together;

The piston28isjreturnedby meansof the compression spring 25} and asuitable bleed-- ing port"'46 around thevalvestem40 may be 'prc'avided. It will also'bejseenthat the'piston chamber 22 as providedwith I ashoulder 2'0" limiting the. forward movement of the piston', and inasmuch as the die 26 is' spaced a predetermined"distance from the hook 31 claims or the requirements of the prior art.

What I claim is:

1. The combination of a die, means for holding the work against the thrust of said die, said means comprising a hook adapted to penetrate a plate presented edgewise to said die, and means for moving the die relatively to the hook to bend the edge of said plate.

2. A curling tool comprising, in combination a support, a reciprocating die having means for curling the free edges of a pair of superimposed plates over the edges of a pair of panel flanges, and means carried by said support for holding said plates in position between said flanges during the operation of the die.

3. A curling tool comprising, in combination a support, a reciprocating die having means for curling the free edges of a pair of superimposed plates, and means carried by said support and projecting through said plates for holding the same in position relatively to said die.

4. A tool for bending the free edges of a pair of superimposed molding strips over the edges of a pair of panel flanges between which the molding strips are interposed, and comprising a tool support having a hook insertable through a hole in said strips and flanges, and a die member movable toward said hook for bending the edges of said strips.

5. A tool for bending the free edges of a pair of superimposed molding strips over the edges of a pair of panel flanges between which the molding strips are interposed, and comprising a tool support having a hook insertable through a hole in said strips and flanges,

a die member movable toward said hook for bending the edges of said strips, and pneuigiatic mechanism for operating said die mem- 6. A tool for oppositely bending the free ing a hole therethrough located in rear of said free ends and comprising a fixed mem ber insertable through said hole and a die member movable relatively thereto for bending over said free ends.

7. In a tool of the class described, the combination of a support, a projecting member carried thereby and adapted to extend through alined holes in two pairs of superimposed plates, a die carried by said support ends of a pair of superlmposed plates havand shiftable toward said member for bending the edges of the intermediate pair of plates over the edges of the outer pair of plates, and means for operating said die.

8. In atool of the class described, the combination of a support, a projecting member carried thereby and adapted to extend through alined holes in two pairs of superimposed plates, a die carried by said support and shiftable toward said member for oppositely bending the edges of the intermediate pair of plates over the edges of the outer pair of plates, said die having a wedge forseparating the edges of the plates, and means for operating said die.

9. The combination of a tool support, a shiftable die member carried thereby and having means for bending over in opposite directions the free ends of a pair of superimposed plates, and a stationary hook carried by said support and comprising a stud projecting at right angles to the path of movement of said die member and in advance. thereof and adapted to engage said plates. I

10. A pneumatic tool comprising a reciprocating hammer having means for separating and curling in opposite directions the free edges of a pair of plates, and a stationary means in advance of said hammer for holding said plates in position and comprising a stud extending transversely to the path of operation of said die member.

11. A tool for bending the free edge of a molding strip over the edges of a pair of panel flanges between which a portion of said molding strip is interposed, said tool comprising, in combination a bending die, means engaging the interposed portion of said strip for holding the latter against the thrust of said die, and means for relatively moving said die and member toward one another.

12. A tool for forming a panel joint including a pair of panels having inturned flanges and a molding strip having a head engaging the outer faces of said panels and a flange interposed between said panel flanges and extending inwardly beyond the same, said tool comprising, in combination a bending die, means engaging said molding flange for holding the latter against the thrust of said die, and means for relatively moving said die and engaging means toward one another to bend portions of said molding flange outwardly over the inner edges of said panel flanges and simultaneously exert an inward reaction upon said molding to draw the head thereof into close engagement with said panels.

In testimony whereof I aflix my signature.

OTTO JOHN GROEHN. 

